Question

32 A sum of money become 4 times after a time period at the rate of 4%. calculate the time.
​

Answer 1

Answer:

Let P Rs be the sum. Let it become 4P Rs after T years.

Simple interest = 4P-P = 3P Rs

Rate percent R = 6%.

SI = PTR/100

3P = PT6/100

3 = 6T/100

6T = 300

T = 50

Answer 2

Given :- A sum of money become 4 times after a time period at the rate of 4%. calculate the time.

Solution :-

when rate is at simple interest :-

→ Time = (SI * 100) / (P * R)

→ Time = [(Times - 1)/Rate] * 100

→ Time = {(4 - 1)/4} * 100

→ Time = (3/4) * 100

→ Time = 75 years (Ans.)

when rate is at compound interest :- Let sum is P and Time is T years . sum becomes 4 times that will be 4P .

so,

→ 4P = P[1 + (4/100)]^T

→ 4 = (26/25)^T

taking log both sides,

→ log 4 = T(log 26 - log 25)

→ T = log 4 / (log 26 - log 25)

→ T ≈ 35 years (Ans.)

Learn more :-

CI in 2yr is Rs. 1600 and in 3 yrs it will be Rs. 1700. Find the rate of interest.

https://brainly.in/question/32463301

7. Abhishek invested some amount for 3 yrs at rate of 16(2/3)% per annum at Cl. The difference of CI obtained

only on 3r...

https://brainly.in/question/38286271